Meinl SB305 Cajon Brush

Great tools, they save your hands and back: you can sit more upright (less hunched); and when switching between cájon and violin, my fingers don't feel as numb.

The rubber rings are adjusted easily and give you the choice between a harder punch / snare, and a softer, more jazzy sound. (Though for even more of that, wire or other brushes are even better).

Another review (in Italian) mentioned that the tips deform / bend on louder playing: this is true. But this doesn't seem to be a problem, and they can be bent back straight -- for now at least, maybe this doesn't work anymore after longer use.